The salvage businesses buying these are going to end up regulated like pawn shops I have sold cats off cars before after doing downpipes on them. They often give you more than the cost of the downpipes back in value. I can see how this is very lucrative and open to abuse. Big issue in the UK and US where people park outside overnight or don't have real security. However, it would not surprise me if people in SA didn't even realise they had been scammed and independent shops or panelbeaters were cutting out cats and replacing them with straight pipes. I say this because in SA, it doesn't seem many cars actually throw emissions lights in a hurry. It's been like this on Alfa, BMWs, Subarus and Hondas as well and even if they would, it would be worthwhile just doing the cat foolers as the salvage agents buy these no-questions-asked and for large enough amounts of money.
It's also how performance shops do those "R5000 for software and downpipe" specials... then come with stories about how they had to cut the flanges off your original so it was scrap... and use your cat as their actual profit

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